This invention relates to a warning light system and more particularly to an array of synchronous flashing warning lights for signaling a hazard or the like on a highway, for example.
Warning lights are extensively used on highways and on construction sites to signal certain hazardous conditions or areas to be avoided. A warning light of the type under consideration for the purposes of this invention is disclosed in U.S. Pat. No. 3,500,378. These warning lights are generally arranged to gain attention by causing the lamps to flash periodically. These flashing warning lights may be arranged in an array to outline the area to be avoided or to signal to a motorist a lane change must be made. When the warning lights that are arranged in an array flash in a random fashion without reference to the flashing of any other light in the array, this mode of operation produces what is known as a "firefly" effect. Attempts have been made by prior art techniques to provide a warning light system through the use of such flashing or blinking lights but to cause them to synchronously flash. The prior art techniques that have been employed generally employ a master/slave relationship for achieving the synchronous flashing of the warning lights. One prior art example of this master/slave technique is disclosed in U.S. Pat. No. 3,787,867. These implementations generally require a single master transmitter for transmitting a signal to all of the lights in an array to cause the lights to flash in synchronism only in response to the signal transmitted from the master transmitter. These master/slave techniques generally require a precision oscillator to be employed in the master transmitter. The warning lights are also generally coupled together by connecting lead wires which makes it more difficult to readily arrange the warning lights in an array.